The future of green energy is written in the wind.
As the U.S. energy industry inches away from reliance on fossil fuels, experts have heralded various greener technologies, such as ethanol, solar and geothermal power, as choice alternatives. And while each of those alternatives holds marked environmental advantages over dirty oil and coal, none match wind power’s squeaky clean performance.
“Based on the review looking at the major energy technologies and environmental impact, wind came out on top,” said Mark Z. Jacobson, an engineer at Stanford University. “But it was pretty close with concentrated solar, geothermal, tidal, wave and hydroelectric sources.”
Last year, Jacobson and a colleague from the University of California, Davis, drafted a global blueprint for converting 100 percent of the world’s energy use to renewable sources. Wind power is leading the charge due to its minimal carbon footprint compared to energy output.
In a nutshell, wind power systems consist of tall, free-standing turbines that convert moving air into usable electricity. As wind pushes the turbine blades around, the spinning motion turns the turbine rotor, which then drives the shaft of an electric generator housed within the turbine. Transmission lines can then deliver the wind-generated electricity from prime wind energy areas, like the Great Plains, to various locations.
In fact, just 15 percent of the land on Earth has enough wind speed capacity to meet global energy needs many times over, Jacobson said.
Related Links:
- Top 10 Countries with the Largest Capacity of Wind Energy
- HOWSTUFFWORKS: How Wind Power Works
- Airborne Wind Turbines Lift Off
- QUIZ: Test your knowledge about wind energy.
Consequently, U.S. energy policy calls for 20 percent of the nation’s total energy use to come from wind power by 2030, which is a modest proposal in light of its impressive potential.
“You can power the entire U.S. vehicle fleet if you converted it to electric with about 100,000 5-megawatt wind turbines,” Jacobson told Discovery News.
The actual ground space required for such a project? According to Jacobson’s calculation, less than 2 square kilometers.
That doesn’t include the spacing between turbines, but well-designed wind power systems can preserve the integrity of green space surrounding turbines and minimize any disruptions to indigenous wildlife, especially compared to habitat destruction associated with coal mining and fossil fuel drilling.
“The land area required for wind is by far the lowest of all alternative energy technologies. It’s just the turbine touching the ground,” Jacobson said.
As wind energy technology improves, offshore turbines situated in the ocean could further reduce the total land space required for wind energy systems.
“It’s easier and, so far, less costly to install wind turbines on land than to install them offshore,” said James Manwell, director of the Renewable Energy Research Laboratory at the University of Massachusetts, Amherst. “The cost difference will probably go down as the offshore technology is further developed, but the ocean will always be a difficult environment.”
Whether on land or in sea, once turbine and transmission systems are in place, wind harvesting relies on no other natural resources, such as water required to irrigate fields for ethanol manufacturing, and produces virtually zero carbon emissions.
Even after wind turbines reach the end of their 30-year lifecycles, the materials can be recycled.
“The required time, in terms of months of operation, to pay back the energy used in the production of a wind turbine is less than most other renewable energy options, such as photovoltaics,” Manwell told Discovery News.
And speaking of payback, the wind technology developments over recent decades have drastically lowered the associated costs, which is why wind energy has been the second-largest new source of electric power after natural gas for the past four years.
But due to still competition from other energy sectors and a lack of a cohesive government push toward wind energy development, the U.S. has a long way to go in order to meet that goal of 20 percent wind power by 2030.
“Technically, it’s certainly feasible to supply 20 percent -- and actually even more -- of U.S. electricity from the wind by 2030,” Manwell said. “The question is, does the U.S. have the political will to do so?”
Meeting that marker demands a laundry list of additional efforts, Manwell says, including educating the public and legislators on the environmental value of wind energy, retraining manufacturers to facilitate wind energy capture and providing government incentives for building wind turbine systems.
Jacobson at Stanford University exhibits similar reservation when forecasting the future of wind energy.“It’s certainly feasible,” Jacobson explained. “It’s technically feasible to have 50 percent or more. It just becomes again an issue of politics because to promote something like that you need subsidies, political willpower and a plan at a government level.”
But considering wind energy’s bright green track record and power supply potential, he remains hopeful that favorable political winds will blow in its direction.
“I’m going to be optimistic and say ‘yes’ (the U.S. can achieve the 20 percent goal), but obviously there’s uncertainty,” Jacobson said. “Not technical uncertainty, but uncertainty about policy.”
Credit: Thinkstock Images/Getty Images
Tags: Alternative Power Sources, Carbon Emissions, Carbon Footprint, Conservation, Energy
comments ( )